GPT-5.5 leaks reasoning traces in Codex

// 49d agoSECURITY INCIDENT

GPT-5.5 leaks reasoning traces in Codex

A Reddit user says GPT-5.5-medium in Codex surfaced what looks like internal planning text while handling a coding task. The report is anecdotal, but if reproducible it points to a safety and UX bug in how Codex separates private scratchpad output from user-visible responses.

// ANALYSIS

This reads less like a dramatic model breakthrough and more like an agent wrapper failing to keep its private notes private.

–The reported output looks like fragmented planning and formatting instructions, which suggests internal reasoning or orchestration text may have been exposed
–Because this is a single Reddit report, it should be treated as a user-observed bug, not a confirmed systemic vulnerability
–If reproducible, the issue matters more for trust than correctness: coding agents need hard boundaries between hidden planning and final answers
–OpenAI explicitly pushed GPT-5.5 into Codex for agentic coding on April 23, 2026, so any trace leakage lands in a high-stakes workflow
–The linked LocalLLaMA discussion shows this kind of prompt/format leakage has been a recurring community concern for months

// TAGS

gpt-5.5ai-codingcoding-agentagenttool-usesafetysecurity

DISCOVERED

49d ago

2026-05-03

PUBLISHED

49d ago

2026-05-03

RELEVANCE

9/ 10

AUTHOR

Homeschooled316

// KEEP READING

More AI developer news from the feed

EXPLORE FULL FEED

VIDEO52m ago

Claude Code, Bun creators demo autonomous loops

This 20-minute talk by Boris Cherny (Head of Claude Code at Anthropic) and Jarred Sumner (creator of Bun) details their transition from manual coding to fully autonomous developer workflows. They showcase "RoboBun," an agentic setup using Claude Code to reproduce issues, generate regression tests, and manage pull requests, illustrating how developers are shifting from simple chatbot prompts to multi-agent parallel loops for code maintenance.

MODEL1h ago

Gemma 4 12B Fable 5 Composer 2.5 drops

Gemma 4 12B Agentic Fable 5 Composer 2.5 is a community-developed fine-tune of Google's Gemma 4 12B instruct model, optimized for local coding, tool use, and multi-step agentic workflows. Leveraging distilled reasoning traces, the model claims a 3.5x improvement over the base model on local telecom benchmarks, bringing high-fidelity reasoning capabilities to local developer setups.

NEWS2h ago

Givros asks if GPT-5.6 hits OpenAI Codex

AI creator Givros publicly asked OpenAI's Head of Codex Thibault Sottiaux whether the rumored GPT-5.6 model will be integrated into the Codex coding agent platform immediately upon its release. The question underscores the intense community interest in how quickly OpenAI will roll out new model capabilities to its developer tools amidst rumors of GPT-5.6's testing and impending launch.

GPT-5.5 leaks reasoning traces in Codex